The present invention relates to a spinning machine and more specifically to a ring-type spinning machine for spinning yarns comprised of finite length fibers, preferably carded wool. The machine is provided with a plurality of spinning locations at each of which two textile fiber strands are run together at a joining point after leaving a drawing machine at spaced locations as untwisted fiber strands and are twisted together to form a yarn upon travel to a spindle or the like. A sensor is associated with each spinning location which reacts to a break of one of the two fiber strands by interrupting the spinning of the yarn.
The twisting of the yarn can be produced by conventional means, preferably by means of a spindle which is located coaxially within a spinning ring upon which a runner carried by the yarn travels during winding of the yarn on the spindle. It is also possible to provide other devices for producing the twist and for winding up the yarn such as a rotating spinning head, a wing spindle or the like.
The interruption of the spinning of the yarn after one of the two fiber strands breaks is desirable because the yarn spun after the break in one of the fiber strands, has only half the mass per unit length. In further processing of the yarn, this weak point may easily lead to yarn breaks and low quality goods. Each working location of the spinning machine where yarn is produced is designated hereinafter as a spinning location.
In prior art spinning machines of this type, such as that disclosed in German Utility Model 79 12 423 a sensor is associated with each spinning location and is provided with a yarn guide which is movably supported between two positions on a holder and which is held in balance in the first position and can be moved out of this balanced position to a new position limited by the influence of the yarn passing therethrough. However, when these movement limits are exceeded upon breaking of one of the two fiber strands, a break is produced in the remaining strand travelling to the spindle by the yarn guide pivoting downwardly in a vertical plane by about 180.degree. or horizontally by about 90.degree.. This causes the remaining strand to be diverted by the yarn guide through a sharp acute angle which sooner or later results in the breakage of this remaining strand. There is no guarantee, however, that this break will actually occur because the twisting imparted to this remaining strand by the spindle may extend through the yarn guide clear back to the drawing machine. In addition, even if the remaining strand does indeed break, the period of time before the break occurs can vary greatly and cannot be predicted ahead of time.